Blood Pressure Surge Research Articles

Relationships among intensive blood pressure control, morning blood pressure surge and 24-hour blood pressure variability

Abstract Objectives This study aimed to investigate the relationships between cardiovascular outcomes and blood pressure (BP) reduction, 24-hour BP variability (BPV), morning BP surge (MBPS), and visit-to-visit BPV. Methods This study involved 897 participants from the Systolic Blood Pressure International Trial (SPRINT), for whom biochemical and demographic data, medication history, and various blood profile information were collected. Univariate and multivariate linear regression models were used to assess the impact of intensive BP management on 24-hour BPV and the MBPS. Results Among the 897 participants (average age 71.48 ± 9.42 years; 640 males), 453 received intensive treatment. Those in the intensive group were more likely to be on ACE inhibitors, CCBs, or diuretics. This group showed significant reductions in 24-hour systolic and diastolic BP, as well as in both short-term and long-term BPVs, such as average real variability (ARV) and MBPS. The analysis demonstrated strong associations between intensive BP management and improvements in various BPV measures, including systolic ARV, diastolic BP ARV, and cumulative BP loads. A significant correlation was also found between intensive BP lowering and the primary composite outcome of the SPRINT study. Conclusions This study highlighted the significant associations between intensive BP management and reductions in the MBPS and 24-hour BPV, which affect both short-term and long-term health outcomes. The primary benefits of intensive BP control appear to stem from direct BP reduction rather than changes in BPV. However, further extensive randomized controlled trials are needed to confirm these findings.

Neuroprotective agents ineffective in mitigating autonomic dysreflexia following experimental spinal cord injury

Background and objectivesLoss of supraspinal cardiovascular control and secondary damage following spinal cord injury (SCI) lead to cardiovascular dysfunction, where autonomic dysreflexia (AD), triggered by stimuli below the injury, can cause uncontrolled blood pressure (BP) surges, posing severe health risks such as stroke and seizures. While anti-inflammatory neuroprotective agents have been studied for motor recovery, their impact on cardiovascular function remains under investigated. The objective was to assess the efficacy of four clinically approved neuroprotective agents in promoting cardiovascular recovery following SCI. MethodsMale Wistar rats received contusion at the third thoracic spinal segment (T3). Fluoxetine, Glyburide, Valproic acid, and Indomethacin were first administered at 1 h or 6 h post-SCI, and every 12 h for two weeks thereafter. Four weeks following SCI, hemodynamics were measured at rest and during colorectal distension. Locomotor function was assessed prior to SCI and weekly for four weeks after SCI, using the Basso-Beattie-Bresnahan (BBB) locomotor scale. Quantitative comparisons of lesion area were performed. ResultsContrary to the published literature, Indomethacin and Valproic acid resulted in high morbidity and mortality rates 60 % and 40 % respectively) within 2–3 days of administration. Fluoxetine, and Glyburide were well-tolerated. There were no differences in change in systolic BP with colorectal distension compared to control i.e., all experimental groups experienced severe episodes of AD [F(6, 67) = 0.94, p = 0.47]. There was no significant difference in BBB scores in any experimental group compared to control [F(18, 252) = 0.3, p = 0.99]. No between-group differences were observed in tissue sparing at the lesion epicentre [F(6, 422) = 6.98, p = 0.29]. DiscussionDespite promising beneficial effect reported in previous studies, none of the drugs demonstrated improvement in cardiovascular or motor function. Indomethacin and Valproic acid exhibited unexpected high mortality at doses deemed safe in the literature. This emphasizes the necessity for reproducibility studies in pre-clinical research and underscores the importance of publishing null findings to guide future investigations.

RETRACTION: Augmented venoarteriolar response with ageing is associated with morning blood pressure surge.

RETRACTION: Augmented venoarteriolar response with ageing is associated with morning blood pressure surge.

Daytime actisensitivity predicts nocturnal dipping patterns and morning surge in blood pressure: the Home-Activity ICT-based Japan Ambulatory Blood Pressure Monitoring Prospective study.

Ambulatory blood pressure (BP) is influenced by physical activity and the BP response to physical activity (actisensitivity) differs between individuals. This study investigated associations between daytime actisensitivity and nighttime BP dipping status and morning BP surge. Twenty-four-hour ambulatory BP monitoring (ABPM) with simultaneously monitored physical activity using a multisensor all-in-one device (TM-2441; A&D Company) was performed at baseline in HI-JAMP study participants. Those with complete BP measurements and complete physical activity monitoring data were included in this analysis. Actisensitivity was calculated as the slope of the regression line between daytime SBP and log-transformed physical activity over a 5 min period before each BP reading. Hyper and negative reactivity were defined as actisensitivity greater than 90th and less than 10th percentile, respectively. Data from 2692 individuals (mean age 69.9 ± 11.9 years; mean BMI 24.8 ± 4.1 kg/m2, 53.6% men) were analyzed. Those with hyper reactivity had a high prevalence of the extreme dipper pattern of nighttime BP and exaggerated morning BP surge; those with negative reactivity had higher nighttime BP and a riser pattern of nighttime BP. Results remained significant after adjusting for 24-h physical activity. Differences in diurnal BP variability based on actisensitivity were augmented in individuals aged at least 75 years. This study is the first to investigate associations between actisensitivity and 24-h ambulatory BP profiles using an all-in-one multisensor device in a large real-world population. The associations seen between either hyper or negative actisensitivity and abnormal diurnal BP variability, especially in the elderly, could contribute to increased cardiovascular event risk. University Hospital Medical Information Network Clinical Trials Registry, UMIN000029151 (HI-JAMP study).

A CASE REPORT: PHEOCHROMOCYTOMA-INDUCED HYPERTENSION IN A 65-YEAR-OLD PATIENT – AN ANESTHESIOLOGIST’S PERSPECTIVE

Pheochromocytoma is a rare adrenal gland tumor that produces excessive amounts of adrenaline and noradre­naline, leading to a surge in blood pressure. This condi­tion often goes undiagnosed due to its infrequency and diverse symptom presentation, surgery is considered as the definitive treatment. We report a 65-year-old male patient, initially referred to an endocrinologist for further evaluation of a mass in the right kidney discovered via Magnetic Resonance Imaging (MRI), leading to a diagno­sis of pheochromocytoma. Following a successful surgi­cal procedure and peri-operative period, the patient was discharged and advised to return to the hospital 1 month after the surgery and every 1 year for regular follow-ups.

Abstract P381: Sex differences in association between gut microbiome and 24-hour blood pressure variability

Background: Blood pressure (BP) variability is an independent risk factor for cardiovascular disease (CVD). BP variability has been associated with cardiovascular organ damage and is a potential therapeutic target for the prevention of CVD. Recently, the gut microbiome (GM) has been shown to have a pathological role in hypertension, however, the association between GM and BP variability is poorly understood. Methods: 241 community-dwelling individuals free of symptomatic CVD from Hong Kong (113 males and 128 females, mean age 54±6 years) underwent ambulatory BP monitoring and stool microbiota shotgun sequencing. BP variability was determined as systolic/diastolic BP (SBP/DBP) coefficient of variation (CoV), nighttime dipping, and morning BP surge (MBPS). Sleep latency was estimated using 7-day Actigraphy data. Associations of BP variability with GM, and plasma and stool short-chain fatty acids (SCFAs) were analyzed under statistical models adjusting for age, sex, serum glucose and lipids, sodium intake assessed by urine analysis, menopause status, smoking, fatty liver, BP and sleep latency. Results: Women had a significantly higher 24-hour SBP ( p =0.0005) and DBP ( p =0.002) CoV than men. 24-hour SBP CoV had a negative association with GM α-diversity (Shannon and Simpson’s index: all P <0.05) and a positive association with Firmicutes/Bacteroidetes ratio ( P <0.05), suggesting gut dysbiosis in participants with higher systolic BP variability. Several GM species and SCFAs were significantly associated with the indices of BP variability in both men and women. Notably, Parabacteroides merdae had a negative association with both systolic and diastolic BP CoV (all P <0.05-0.01). Bacteroidetes dorei and Bacteroides intestinalis were reduced in women with higher SBP CoV ( P <0.05) and nondipping status ( P< 0.01), respectively. Prewaking and sleepthrough MBPS had a positive association with Faecalibacterium prausnitzii in women (all P <0.001) and plasma acetic acid levels in men ( P <0.05-0.001). Further analysis indicated that Bacteroidetes dorei may mediate SBP CoV via plasma iso-butyric acid in women (bootstrapping 95% CI: -3.6 to -0.19; P <0.05). Conclusions: This cross-sectional study suggests sex-specific associations between GM and BP variability. Most noteworthy, higher systolic BP variability was associated with a significant reduction in potentially beneficial bacterial species, primarily in women which may be explored for therapeutic potential.

Abstract MP01: Clinical Characteristics of Morning Blood Pressure Surge in Patients with Autonomic Failure

Autonomic failure (AF) is characterized by orthostatic hypotension (OH), but most of these patients also have nocturnal supine hypertension (SH), which has been associated with end-organ damage, pressure natriuresis, and worsening of daytime OH. About 30% of patients with SH, however, have a preserved nocturnal BP dipping that is likely associated with a morning BP surge (MBPS). To determine the pattern of MBPS and its association with dipping, natriuresis, and morning OH, we studied 92 AF patients (67±1 yr, 59% males; 32 multiple system atrophy and 60 peripheral autonomic failure [pAF]). Patients were studied off BP medications and placed on a low monoamine, caffeine-free diet containing 150 mEq/d sodium and 70 mEq/d potassium. Nocturnal BP was assessed every 2 hours from 8pm-8am, followed by a 10-minute standing test. Urine was collected for 24 hours and divided into two 12-hour periods. As expected, we found that dipping (systolic BP [SBP] fall ≥10% during nighttime sleep [12am-6am] from baseline [8pm to 10pm]) occurred in 33% of patients, with an average decrease of 35±5 mmHg at 4am. The MBPS (SBP increase at 8am from the average of 3 nighttime SBPs centered on the lowest one) was 10±2 mmHg (range -83 to 77 mmHg; MBPS≥ 20 mmHg, 23%). MBPS was negatively correlated with the magnitude of dipping (r=-0.328, p<0.001; dippers 18±3 vs. nondippers 6±3 mmHg; p=0.010) and mean nighttime SBP (r=-0.230, p=0.028). The night-to-day ratio of sodium (r=-0.417, p=0.002) and urine (r=-0.292, p=0.037) excretion was also negatively correlated with MBPS, indicating that patients with greater MBPS had decreased natriuresis during the night compared to the day. In the morning, a greater MBPS was associated with a larger SBP drop on standing (r=-0.242, p=0.034). No associations were found between MBPS and age, sex, history of essential hypertension, or the underlying diagnosis of AF. To assess the hemodynamic mechanisms of the MBPS, we studied 17 AF patients (67±2 yr, 14 males, all pAF). We found that MBPS (13±5 mmHg, range -18 to 56 mmHg) was associated with an increase in systemic vascular resistance (SVR, r=0.777, p=0.01) and a higher augmentation index (Aix@75, r=0.516, p=0.049). In conclusion, a subset of AF patients had a preserved dipping pattern and an MBPS despite severe impairment of BP regulation. MBPS was associated with increased SVR, lower nighttime SBP, and lower night-to-day natriuresis, but the higher supine SBP in the morning was associated with worse OH.

Prognostic value of morning blood pressure surge in chronic kidney disease.

This was a retrospective study. This study investigated the occurrence of a composite endpoints (cardiovascular and cerebrovascular events, end-stage renal disease, and death) in 153 patients (aged≥18years) with a diagnosis of in chronic kidney disease (CKD). Based on morning blood pressure surge (MBPS) defined as ≥35mm Hg, patients were divided into two groups: with MBPS (n=50) and without MBPS (n=103). All patients were followed up for at least 1year. Baseline demographic, laboratory and follow-up data were collected. The clinical characteristics of the two groups were compared. The relationships between MBPS and endpoint events were analyzed using the Kaplan-Meier method and Cox regression model. In total, 153 patients (mean age 41.8years; 56.86% males) were included in this study. During the follow-up period (mean 4.3years), 34 endpoint events occurred. After adjustment for the covariates, the risk of cardiovascular and cerebrovascular events, end-stage renal disease and death remained significantly higher in patients with MBPS (hazard ratio [HR] and 95% confidence interval [CI] 3.124 [1.096-9.130]]) Among the other variables, systolic blood pressure, and night-time and daytime pulse pressures remained significantly associated with outcome in patients of CKD (1.789 [1.205-2.654], 1.710 [1.200-2.437], and 1.318 [1.096-1.586], respectively]. In conclusions, MBPS was identified as an independent prognostic factor for composite endpoint events (cardiovascular and cerebrovascular events, end-stage renal disease and death) patients with chronic kidney disease patients.

Psychological distress, forced awakening, and morning blood pressure surge.

Morning blood pressure surge (MBPS) has been recognized as an independent predictor of cardiovascular disease events. Psychological distress, including anxiety, depression, and perceived stress, and behavioral risk factors, such as poor sleep quality, have been associated with increased MBPS. Elevations in sympathetic activity induced by forced awakening may also contribute to further increases in MBPS. Yet, no examination of the interrelationships among psychological distress, sleep quality, awakening mode (natural vs. forced awakenings), and MBPS has been undertaken. This pilot study aimed: (1) to examine if MBPS differs by awakening mode and (2) to investigate whether psychological distress is associated with MBPS difference between natural and forced awakenings, independent of sleep quality. Thirty-two healthy adults were included in this cross-sectional study. Blood pressure was measured using a beat-to-beat blood pressure monitor over two nights, consisting of one night of natural awakening and one night of forced awakening. Psychological distress and sleep quality were assessed using questionnaires. We conducted paired t-tests (aim 1) and multiple linear regressions (aim 2). MBPS was significantly greater during forced awakening compared with natural awakening. In addition, the MBPS difference between natural and forced awakenings was significantly greater in participants with higher anxiety levels, independent of sleep quality. We found that augmentation of MBPS by forced awakening was significantly greater in individuals who reported higher anxiety levels. Additional research is needed to examine the potential impacts of forced awakening and anxiety on MBPS in a larger sample of individuals at risk for cardiovascular disease.

Blood pressure changes during ketamine infusion for the treatment of depression

ObjectiveThis study aimed to examine blood pressure changes during ketamine infusion for depression and exploring the factors associated with these changes. MethodThis study is a retrospective chart-review of patients with depression undergoing ketamine infusion at Yale Psychiatry Hospital during a 7-year period. Blood pressure (BP) was recorded every 10 min during the infusion. Surges in systolic and diastolic blood pressure (SBP, DBP), along with severe hypertension events, were analyzed in relation to patient demographics. ResultsA total of 138 patients received a total of 2342 infusions. SBP and DBP peaked at 40 min after the start of the infusion with a mean change of 16.0 (SD: 11.2) and 11.0 mmHg (SD: 8.45) respectively. Severe hypertension was observed in 17 patients (12.5%) and 23 infusion sessions (0.98%), occuring more frequently during the first three infusions (43.4%). Age (OR = 1.04 [1.02,1.05], p-value <0.001) was significantly associated with a surge in SBP and all patients with a past medical history of hypertension experienced a BP surge during their infusions. ConclusionKetamine infusions can cause significant blood pressure increases, particularly in older and hypertensive patients, highlighting the need for careful cardiovascular monitoring to mitigate risks during treatment.

The impact of forced awakening on morning blood pressure surge

BackgroundPoor sleep quality can cause an increase in morning blood pressure surge (MBPS), an independent risk factor of cardiovascular disease (CVD) events. Awakening induced by external factors such as alarm clocks, may also contribute to increased MBPS. ObjectivesTo (1) compare the MBPS and sleep quality parameters between natural and forced awakenings and (2) examine the potential impact of forced awakening on MBPS, independent of sleep quality. MethodsThirty-two healthy adults participated in this pilot study, which included one night of natural awakening and one night of forced awakening (i.e., sleep was interrupted by an alarm after five hours). Objective and self-reported sleep quality parameters were measured using a multisensory wristband and sleep diaries, respectively, and beat-to-beat blood pressure variability was assessed using a continuous blood pressure monitor. Analyses included a paired t-test (objective 1) and linear mixed models (objective 2). ResultsParticipants predominantly consisted of young, healthy, and highly educated Asian adults. During the night of sleep with forced awakening, significantly higher MBPS, lower objective wakefulness after sleep onset, and lower self-reported sleep latency were observed, compared to the night with natural awakening. Forced awakening was significantly associated with increased MBPS after controlling for age, sex, mean arterial pressure, and sleep quality. ConclusionsForced awakening may significantly increase MBPS, consequently heightening the risk of CVD events. Study findings should be validated in a larger sample. Further research is also warranted to examine the impact of forced awakening on MBPS in individuals with CVD.

#2249 Morning blood pressure and heart rate surge in peritoneal dialysis patients

Abstract Background and Aims The increased surge of blood pressure (BP) early in the morning and the parallel increase of heart rate (HR) are risk factors for cardiovascular disease in general and CKD populations. Early morning changes in these parameters have not been investigated in peritoneal dialysis (PD) patients. The aim of the study is to correlate the morning fluctuations of BP and HR with left ventricular hypertrophy and cardiovascular risk. Method This was a cross-sectional study of PD patients followed-up in our Peritoneal Dialysis Unit (PDU). At their regular visit to our PDU, a 24-hour ambulatory BP measurement (Mobil-o-graph®) was performed. A diary was given to the patients in order to record the time they performed their evening exchange (continuous ambulatory peritoneal dialysis- CAPD) or connection to the automated peritoneal dialysis (APD) machine, the time they laid down, the time they approximately fell asleep, when they woke up in the morning, when they inclined from the bed and the time they performed the morning exchange or disconnection. The 24-hour BP recordings were analyzed in the available software and calculations were done based on the diary information; pre-awakening BP, HR surges, nocturnal dipping, weighted 24 h systolic BP and HR variability. Demographic, laboratory data and left heart hypertrophy parameters of the patients were also recorded. 35 patients were eligible for participation in the study; 2 denied participation, 1 was rejected due to ongoing cancer therapy and two patients were declined due to invalid BP measurements. Finally 30 patients (10 males and 20 females) were analyzed, 9 were on CAPD and 21 were on APD. Results The mean age of the patients was 60.5 ± 12.6 years old and the median PD vintage was 21.5 months (8.25-58) (Table 1). Left Ventricular Mass index (LVMi) was 99.01 ± 28 g/m2 (Table 1). The 24h systolic BP was 125.66 ± 10.9 mmHg and the diastolic BP was 79.59 ± 7.7 mmHg (Table 2). The mean pre-awaking Systolic BP surge was 10.76 ± 9.7 mmHg, the median non-dipping blood pressure 8.6 (IQR 1.11-12.86), the mean heart rate surge was 3.3 ± 4.7 /min and the mean non-dipping HR was 9.7 ± 5.9/min (Table 2). There was no statistically significant correlation of the parameters above with the LVMi. Patients with high cardiovascular risk (diabetes, coronary heart disease, heart failure) had statistically higher non-dipping BP (27 vs 12.3 mmHg, p = 0.034) and higher nighttime SPB (27 vs 20.74 mmHg, p = 0.024). When compared patients in CAPD vs APD, there were no differences in the pre-awaking BP or the rest of the measurements performed, although APD patients recorded interrupted sleep due to the alarms of the APD machine. Conclusion PD patients with high cardiovascular risk had higher nondipping BP and nighttime systolic BP compared with patients without cardiovascular disease. There were no correlations of BP and heart rate morning surge with left ventricular hypertrophy or PD mode.

#2227 Exploring the interplay between gut microbiome, fecal metabolomics and ambulatory blood pressure in white-coat hypertensive patients

Abstract Background and Aims Recent evidence showed the relationship between gut microbiota with hypertension. Few studies also demonstrated that ambulatory blood pressure monitoring variables such as dipping status and linear variability are associated with fecal microbiota and metabolomics. However, the relationship between gut microbiota and metabolomic composition of white-coat hypertensive patients has not been studied yet. In addition, although the link between gut microbiota, blood pressure variability and high salt intake has been shown, none of the studies addressed these changes simultaneously in the same study population. Here, we aimed to investigate the interplay between the gut microbiome, fecal metabolites and 24-hour urine sodium levels between hypertensive, white-coat hypertensive (WCH) and healthy participants diagnosed with ambulatory blood pressure monitoring. Method The study included 18 newly diagnosed hypertensive, 8 WCH, and 21 healthy participants from our tertiary center. Ambulatory blood pressure (BP) monitoring was performed in all participants and nighttime dipping, morning BP surge (MBPS), pre-wake MBPS and linear BP variability were calculated. 16S rRNA sequencing was performed using Illumina MiSeq sequencer. DeSeq2 and linear discriminant analysis effect size (LEfSe) were performed with R. Fecal metabolite levels were analyzed by GC-MS. A partial least squares-discriminant analysis (PLS-DA) model was constructed for the feature selector and classifier. The variable importance in the projection (VIP) coefficient was calculated based on the PLS-DA model. Results ANOVA and post-hoc Tukey test showed WHC and hypertensive groups had higher blood pressure variability and morning-thorough MBPS than normotensive patients (p = 0.02 and 0.04, respectively), whereas 24-h urine Na levels were statistically similar between WCH and hypertensive groups (p = 0.11). There were no significant differences in α- and β-diversity metrics of gut microbiome between study groups. Select taxa were specific to WHC patients, notably Rikenellaceae family and Mitsuokella were higher in WHC against normotensive patients, whereas Ruminococcus callidus, Roseburia, Clostridium, Lactobacillus ruminis, Sutterall, Lachospiraceae and Muribaculaceae were decreased in WHC against normotensive patients in DeSeq2 analysis. Dialister was increased, whereas Bacteroides genus and Bacteroides fragilis were decreased in WHC against hypertensive patients. LEfSe analysis showed positive enrichment in Proteobacteria phylum and negative enrichment in Mitsuokella genus in WHC against hypertensive group. Enterococcus, Lachnobacterium, Odoribacter and Pseudomonas genera had positive; whereas Lactobacillus and Clostridium had negative correlations with 24-h urine Na levels. Positive correlations were shown between linear BP variability and Bacteroides and Paraprevotella genera. Several genera and species were enriched in Q3-4 against Q1-2 quartiles of pre-wake and sleep-thorough MBPS in LEfSe analyzes (Fig. 1). Normotensive and essential hypertensive groups could also be differentiated based on fecal metabolomic composition. Specifically, metabolites with the highest VIP values discriminating WCH from normotensive and hypertensive groups were methyl-palmitoleate, oxalic acid and phenyl β-D-glucopyranoside, respectively (Fig. 2). Conclusion In conclusion, we performed the first study focusing on the fecal microbiome and metabolomic characteristics of white-coat hypertensive patients. Urine Na levels and ambulatory blood pressure variables of the WCH group are different than those of the normotensive and similar to the hypertensive group. Comparative and correlation analyses revealed novel relationships between ambulatory blood pressure variables and gut microbiome of both WCH and hypertensive patients. Fecal metabolomic differences between study groups imply possible mechanisms underlying the effects of gut microbiome on blood pressure. Gut microbiota and metabolites may become valuable targets for interventions of both white-coat and essential hypertension in the near future.

The surge in heart rate and blood pressure at respiratory event termination is dampened in children with down syndrome

BackgroundChildren with Down syndrome (DS) have a high prevalence of sleep disordered breathing (SDB) and altered cardiovascular autonomic control. We aimed to analyze the effect of DS on the surge in heart rate (HR) and pulse transit time (PTT, an inverse surrogate measure of blood pressure change) at respiratory event termination. Methods44 children (3–19 y) with DS and 44 typically developing (TD) children matched for SDB severity, age and sex underwent overnight polysomnography. Multilevel modelling determined the effect of DS on HR and PTT changes between a 10s pre-event to the latter half of each respiratory event (late-event) and 15s post-event during NREM and REM, accounting for SDB severity and event length. ResultsThe children with DS had a significantly smaller % change in HR late-event to post-event (NREM: DS 26.4 % ± 17.5 % (mean ± SD), TD 30.7 % ± 21.0 %; REM DS 16.9 % ± 15.3 %, TD 21.0 % ± 14.0 %; p < 0.05 for both) compared with TD children for obstructive events, and central events (13.2 % ± 17.0 %, TD 18.8 % ± 17.0 %; p < 0.01) during REM. %change in PTT was significantly smaller in the DS group during NREM and REM from pre-event and late-event to post-event compared with TD children for obstructive and central events. ConclusionThese results suggest children with DS have dampened HR and BP responses to respiratory events compared with TD children. Whether this is symptomatic of autonomic dysfunction or a protective factor for the cardiovascular system in children with DS remains to be elucidated.

BLOOD PRESSURE SURGE DURING THE EARTHQUAKE IN CITY OF PETRINJA, BANIJA REGION IN CROATIA

Objective: Stress is known to contribute to other well-known environmental risk factors to hypertension leading to sympathetic overactivity. While usual environmental factors can be easily measured, exposure to stress is difficult to objectivize, especially during catastrophic events which are recognized as main stressors. There are several reports about earthquakes, blood pressure (BP) and cardiovascular events. Design and method: We are reporting a case on ambulatory blood pressure monitoring (ABPM) in 42-year-old women during Croatian earthquake. Results: A 42-year-old women with multiple genetic and environmental risk factors for hypertension was evaluated for secondary hypertension, and adult autosomal polycystic kidney disease was diagnosed. Kidney function was normal and there were no signs of target organ damage. She was treated with a fixed dose combination perindopril/amlodipine 4/5 mg (morning). ABPM revealed mildly uncontrolled systolic-diastolic hypertension with extreme nocturnal dip. Average 24-hour, daytime and nighttime BP values were 130±20,4/79±19,9 mmHg, 137±16,2 /85±17,9 mmHg, 100±11,8 /55±11,7 mmHg, respectively. White coat effect was present, and masked hypertension was ruled out. Average 24-hour, daytime and nighttime heart rate were: 88b/min, 93b/min, and 79b/min. A significant surge in BP and heart rate (200/130 mmHg,140 b/min) was recorded at 12:30 p.m. exactly at the time when earthquake occurred in city Petrinja, also felt in Zagreb city. The earthquake was clearly stated in the blood pressure diary (Figure 1). Conclusions: Although chronic stress is emphasized to affect human health more than acute, catastrophic events such as earthquakes can have deleterious effect such as enormous elevation of BP. It is necessary to have strategies for BP management in disaster-related diseases to prevent organ damage.

Circulatory Effects of Peripheral Chemoreflex Inhibition During Exercise in Treated Hypertension

The sensitization of the peripheral (carotid) chemoreflex can cause a sympathetically mediated restraint of blood flow to the exercising muscles in some disease states (e.g., heart failure, COPD). Such impairments in nutritive blood flow have the potential to impair exercise tolerance and raise exercising blood pressure (BP). Increased peripheral chemoreflex sensitivity and pronounced exercise-induced surges in BP have been reported in hypertension. Herein, we tested the hypothesis that suppressing peripheral chemoreflex sensitivity improves skeletal muscle blood flow during exercise in hypertension. Fourteen patients with treated hypertension (age 69±11 years, systolic BP 136±12 mmHg, diastolic BP 80±11 mmHg; mean ± SD) performed a resting baseline (3 min), an isocapnic hypoxia rebreathing test and rhythmic handgrip exercise (3 min at 50% of maximal voluntary contraction, 1 s contraction and 2 s relaxation) with either intravenous 0.9% saline (control) or low-dose dopamine (2 mcg·kg−1·min−1) to inhibit the peripheral chemoreflex. BP (finger plethysmography), heart rate (HR; electrocardiogram) and ventilation (V̇E; heated pneumotachometer) were recorded throughout. Brachial artery blood flow was monitored (duplex Doppler ultrasound) at rest (1 min average) and during handgrip (15 s averages), and vascular conductance calculated as brachial blood flow/mean BP. Dopamine blunted the peak (last 15 s) increase in V̇E during isocapnic hypoxic rebreathing compared to saline infusion (Δ6±6 vs. Δ9±5 L·min−1, P=0.026), while also attenuating peak mean BP (Δ3±4 vs. Δ8±6 mmHg, P=0.007). Dopamine did not change resting mean BP (95±10 vs. 98±10 mmHg, P=0.155) and HR (68±7 vs. 66±8 beats·min−1, P=0.100). However, dopamine increased resting brachial blood flow (59±20 vs. 48±16 mL·min−1, P=0.030) and vascular conductance (0.565±0.246 vs. 0.483±0.160 mL·min−1·mmHg−1, P=0.039) and decreased resting V̇E (10.5±3.2 vs. 11.5±3.1 L·min−1, P=0.036) versus saline. Handgrip increased brachial artery blood flow (p&lt;0.05 vs. rest after 45 s), vascular conductance (p&lt;0.05 vs. rest after 45 s) in both saline and dopamine trials, while mean BP, HR and V̇E were unchanged (main effect of time P=0.829, P=0.954 and P=0.255, respectively). Notably, brachial artery blood flow (e.g., Δ76±54 vs. Δ60±43 mL·min−1 at 60 s) and vascular conductance (e.g., Δ0.730±0.440 vs. Δ0.570±0.424 mL·min−1·mmHg−1 at 60 s) responses to handgrip were greater with dopamine than saline (main effect of condition both p&lt;0.0001). Collectively, these findings indicate that the use of low-dose dopamine to suppress peripheral chemoreflex sensitivity improves skeletal muscle blood flow during rhythmic handgrip exercise in patients with treated hypertension. Funding support provided by the Health Research Council of New Zealand (19/687) and the Sidney Taylor Trust. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

The Option of Chronotherapy of Hypertension.

The aim of the present paper is to explore the option of chronotherapy of hypertension and its effectiveness in blood pressure (BP) lowering compared with its standard daily treatment. The treatment of BP has gone through many different schemes over the years. From no treatment in the early 1930s, to step care, to multiple drug combinations, or to single daily drug combinations with 2-3 drugs, still BP is not well controlled in a significant number of patients. Recently, the role of the circadian rhythm in the treatment of hypertension has been tested by several studies comparing the evening versus the morning drug administration with no clear evidence of superiority of either mode of drug administration. However, in cases of morning surge of BP, nocturnal hypertension, and renal disease, the evening drug administration has been more effective than the morning drug administration, and thus, more preferable. In order to get a better perspective on this approach of hypertension treatment, a Medline search of the English literature was contacted between 2010 and 2023 using the terms BP control, circadian rhythm, morning drug administration, evening drug administration, and 38 pertinent papers were selected for analysis. Careful review of the selected papers showed that chronotherapy of hypertension is effective. However, the overall effectiveness of evening drug administration compared with the morning administration is not significantly more effective compared to the morning administration and more work is needed in this field.

Circadian and Diurnal Regulation of Cerebral Blood Flow.

Circadian and diurnal variation in cerebral blood flow directly contributes to the diurnal variation in the risk of stroke, either through factors that trigger stroke or due to impaired compensatory mechanisms. Cerebral blood flow results from the integration of systemic hemodynamics, including heart rate, cardiac output, and blood pressure, with cerebrovascular regulatory mechanisms, including cerebrovascular reactivity, autoregulation, and neurovascular coupling. We review the evidence for the circadian and diurnal variation in each of these mechanisms and their integration, from the detailed evidence for mechanisms underlying the nocturnal nadir and morning surge in blood pressure to identifying limited available evidence for circadian and diurnal variation in cerebrovascular compensatory mechanisms. We, thus, identify key systemic hemodynamic factors related to the diurnal variation in the risk of stroke but particularly identify the need for further research focused on cerebrovascular regulatory mechanisms.

Effects of a maintenance period on ambulatory blood pressure and morning blood pressure surge in young normotensives post isometric training.

Isometric resistance training (IRT) has emerged as an efficacious therapeutic intervention to reduce ambulatory blood pressure (BP), and BP diurnal variability. However, once the required decreases in BP have been achieved the efficacy of implementing a reduced maintenance dose is not understood. Therefore, the purpose of this study was to determine the effects of an 8-week maintenance period (8-week) following the cessation of the prescribed 8-week IRT in young normotensives. Twenty-two recreationally active, not resistance trained, normotensive (24-h ambulatory SBP, ≥130mmHg) young adults were randomly assigned to a training-maintenance [TG-MT; n = 13 (female = 5); age 21 ± 2years] or a non-training control [CON; n = 9 (female = 4); age 23 ± 3years] group. Ambulatory BP, morning BP surge (MBPS) and average real variability (ARV) were measured prior to, after 8 weeks of bilateral leg IRT (4x2-minute contractions at 20% MVC with 2-min rest periods, 3days/week) and following an 8-week (once per week) maintenance period. On completion of the maintenance period the significant reductions seen following the IRT were maintained within the TG-MT group in 24-h ambulatory SBP (6 ± 4mmHg, p < 0.001), daytime (5 ± 5mmHg, p = 0.002), MBPS (7 ± 10mmHg, p = 0.019) and 24-h SBP ARV (2.03 ± 1.44mmHg, p = 0.001), daytime SBP ARV (2.04 ± 1.78mmHg, p = 0.003). These results show that reductions in ambulatory BP (24-h SBP and daytime SBP), in addition to BP diurnal variations (MBPS, 24-h SBP ARV and daytime SBP AVR) are maintained following an 8-week maintenance dose in young adults and add further weight to the growing body of evidence promoting IRT as an efficacious therapeutic exercise intervention to prevent or reduce BP.

Morning blood pressure surge and intracranial atherosclerotic plaque characteristics: a high-resolution magnetic resonance vessel wall imaging study.

To investigate the relationship between morning blood pressure surge (MBPS) and intracranial atherosclerotic plaque burden and vulnerability. A total of 267 ischaemic stroke patients were retrospectively analysed. Sleep-trough and prewaking MBPS were calculated from ambulatory blood pressure monitoring (ABPM). Plaque characteristics, including intraplaque haemorrhage (IPH), maximum wall thickness (max WT), and stenosis degree, were obtained from high-resolution MR vessel wall imaging (HR-vwMRI). Linear and logistic regression were used to detect the association. Subjects with the top tertile of sleep-trough MBPS (≥15.1 mmHg) had a lower prevalence (9.1% vs. 19.6%, P = .029) of severe stenosis (≥70%) than others. Subjects within the top tertile of prewaking MBPS (≥7.6 mmHg) had a lower percentage of IPH (27.3% vs. 40.4%, P = .035) than others. After adjusting for stroke risk factors (age, sex, diabetes, hyperlipidaemia, hyperhomocysteinaemia, smoking, and family stroke history) and 24-h mean systolic blood pressure, 10 mmHg sleep-trough MBPS increment was associated with 0.07mm max WT reduction, and the top tertile MBPS group was associated with a lower chance of severe stenosis (odd ratio = 0.407, 95% CI, 0.175-0.950). Additionally, an increased prewaking MBPS is associated with a lower incidence of IPH, with OR = 0.531 (95% CI, 0.296-0.952). Subgroup analysis demonstrated that the positive findings could only be seen in non-diabetic subjects. Increment of MBPS is negatively associated with intracranial atherosclerotic plaque burden and vulnerability, and this relationship remains significant in the non-diabetic subgroup. This study provided evidence that MBPS was associated with the intracranial atherosclerotic plaque burden and vulnerability on HR-vwMRI.